1 files changed, 9 insertions, 13 deletions
diff --git a/erts/preloaded/src/prim_file.erl b/erts/preloaded/src/prim_file.erl
index 5c9cad3a2c..46ce3ab1a4 100644
--- a/erts/preloaded/src/prim_file.erl
+++ b/erts/preloaded/src/prim_file.erl
@@ -1493,19 +1493,15 @@ to_seconds({_,_} = Datetime, universal) ->
 to_seconds({_,_} = Datetime, local) ->
     erlang:universaltime_to_posixtime(erlang:localtime_to_universaltime(Datetime)).
 
-%% TODO: Duplicate code!
 get_dtrace_utag() ->
-    case get(dtrace_utag) of
-        X when is_list(X) ->
-            X;
-        _ ->
-            ""
+    %% We cannot call dtrace:get_utag() because this is prim_file.erl.
+    %% We must reimplement it here.
+    case get('_dtrace_utag_@_@') of
+        undefined ->
+            <<>>;
+        X ->
+            X
     end.
 
-%% TODO: Measure if it's worth checking (re:run()?) for NUL byte first?
-enc_utag([0|Cs]) ->
-    enc_utag(Cs);
-enc_utag([C|Cs]) ->
-    [C|enc_utag(Cs)];
-enc_utag([]) ->
-    [0].
+enc_utag(UTag) ->
+    [UTag, 0].